The sum of three numbers is 98. If the ratio of the first to the second is 2 : 3 and that of the second to the third is 5 : 8, then the third number is :

48

First  :  Second  :  Third

  2    :       3

                5      :    8

_____________________

 10   :     15      :    24    ⇒ 49R = 98  ⇒ R = 2

Third number = 24R = 24 x 2 = 48